class Company {
    constructor() {
        this.departments = [];
    }
    addEmployee(username, salary, position, department) {
        if ([...arguments].includes(null) || [...arguments].length < 4 || salary < 0) {
            throw "Invalid input!";
        } else {
            const newEmployee = {
                username: username,
                salary: salary,
                position: position,
                department: department
            }
            if (c.departments.filter(function(e) { return e.name === department; }).length > 0) {
                for (let existingDepartment of this.departments){
                    if (existingDepartment.name === department) {
                        existingDepartment.users.push(newEmployee);
                        existingDepartment.totalSalary += salary;
                    }
                }
            } else {
                let newDepartment = {
                    name: department,
                    users: [newEmployee],
                    totalSalary: salary,
                    averageSalary(){return this.totalSalary / this.users.length}
                }
                this.departments.push(newDepartment);
            }
            return `New employee is hired. Name: ${username}. Position: ${position}`

        }
    }

    bestDepartment() {
        let bestDepartment = this.departments.sort((a,b)=>(a.averageSalary  - b.averageSalary))[0];
        bestDepartment.users =  bestDepartment.users.sort(function(a, b) {
            if (a.username === b.username) {
               // Price is only important when cities are the same
               return b.username - a.username;
            }
            return a.salary < b.salary ? 1 : -1;
         });
        let result = `Best Department is: ${bestDepartment.name}\nAverage salary: ${bestDepartment.averageSalary().toFixed(2)}`
        for (let user of bestDepartment.users) {
            result += `\n${user.username} ${user.salary} ${user.position}`
        }
        return result;
    }
}


// let c = new Company();
// c.addEmployee("Stanimir", 2000, "engineer", "Construction");
// c.addEmployee("Pesho", 1500, "electrical engineer", "Construction");
// c.addEmployee("Slavi", 500, "dyer", "Construction");
// c.addEmployee("Stan", 2000, "architect", "Construction");
// c.addEmployee("Stanimir", 1200, "digital marketing manager", "Marketing");
// c.addEmployee("Pesho", 1000, "graphical designer", "Marketing");
// c.addEmployee("Gosho", 1350, "HR", "Human resources");
// console.log(c.bestDepartment());


var assert = require('assert');
//let Company = result;
let c = new Company();

let actual1 = c.addEmployee("Stanimir", 2000, "engineer", "Human resources");
let expected1 = "New employee is hired. Name: Stanimir. Position: engineer";
assert.equal(actual1,expected1);

c.addEmployee("Pesho", 1500, "electrical engineer", "Construction");
c.addEmployee("Slavi", 500, "dyer", "Construction");
c.addEmployee("Stan", 2000, "architect", "Construction");
c.addEmployee("Stanimir", 1200, "digital marketing manager", "Marketing");
c.addEmployee("Pesho", 1000, "graphical designer", "Marketing");
c.addEmployee("Gosho", 1350, "HR", "Human resources");

let act = c.bestDepartment();
let exp = "Best Department is: Human resources\nAverage salary: 1675.00\nStanimir 2000 engineer\nGosho 1350 HR";
assert.equal(act,exp);